diff options
Diffstat (limited to 'lib/clz_ctz.c')
-rw-r--r-- | lib/clz_ctz.c | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/lib/clz_ctz.c b/lib/clz_ctz.c new file mode 100644 index 0000000..a8f8379 --- /dev/null +++ b/lib/clz_ctz.c @@ -0,0 +1,58 @@ +/* + * lib/clz_ctz.c + * + * Copyright (C) 2013 Chanho Min <chanho.min@lge.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + * + * __c[lt]z[sd]i2 can be overridden by linking arch-specific versions. + */ + +#include <linux/export.h> +#include <linux/kernel.h> + +int __weak __ctzsi2(int val) +{ + return __ffs(val); +} +EXPORT_SYMBOL(__ctzsi2); + +int __weak __clzsi2(int val) +{ + return 32 - fls(val); +} +EXPORT_SYMBOL(__clzsi2); + +#if BITS_PER_LONG == 32 + +int __weak __clzdi2(long val) +{ + return 32 - fls((int)val); +} +EXPORT_SYMBOL(__clzdi2); + +int __weak __ctzdi2(long val) +{ + return __ffs((u32)val); +} +EXPORT_SYMBOL(__ctzdi2); + +#elif BITS_PER_LONG == 64 + +int __weak __clzdi2(long val) +{ + return 64 - fls64((u64)val); +} +EXPORT_SYMBOL(__clzdi2); + +int __weak __ctzdi2(long val) +{ + return __ffs64((u64)val); +} +EXPORT_SYMBOL(__ctzdi2); + +#else +#error BITS_PER_LONG not 32 or 64 +#endif |